We know that birds use them to migrate, and apparently, dogs use them to poop, but it seems that wild pigs can also sense the planet's magnetic fields. For the first time, new research suggests that boars and warthogs have their own internal compass that allows them to detect the north-south axis, along which they orientate themselves to forage and move.
The new knowledge of how these animals align along these lines might not seem to have many implications, but with wild boars causing a significant amount of damage not only to crops, but also to safety, as their numbers are increasingly rising across much of Europe, it could give a new way to manage them. Perhaps, it is suggested, that by disrupting the foraging pigs' magnetic fields the animals could be encouraged to go in some areas and avoid going in others.
The research, published in the journal Mammal Review, used data collected from over 1,600 wild boars living in the Czech Republic, along with over 1,300 warthogs in six countries across Africa. The team observed the animals from a distance, and noted their orientation as they started foraging, as well as the alignment of their beds, shallow holes which they scrape out of the ground. It turns out that not only do the pigs forage and move along the north-south axis, but they also sleep like that too.
“Given the well-developed navigation skills of wild boars, it would not be surprising if they made use of a magnetic compass or even a map,” write the researchers. “A magnetic sense would, for example, help boars put several feeding grounds into global perspective, therefore facilitating quick switching between them when needed.” So it seems that the pigs may be using the magnetic field to help them forage, and to that end, it may also come into use to prevent them from doing so.
There is already some evidence that overhead power lines cause some migrating animals' internal compass to go awry, with studies suggesting that birds can be put off, and others finding that caribou may also be affected by the lines. With the number of wild boars exploding in Europe, breeding at a rate much faster than they can be culled, the idea then that this internal magnetic compass could be used to protect crops, or direct the pigs to where humans want them, could hold some traction.